The present invention relates to headphones whose sides opposite the sides to be fitted against the listener's ears, that is, the back sides, are open. More particularly, the invention relates to an open-back type headphone which is so adapted that an attachment for covering the back side thereof can be detachably attached to the back side.
In general, headphones for listening to sounds are of the so-called closed type wherein the backs of the headphone structures, that is, the sides opposite the sides to be fitted against the listener's ears, are closed. In the use of headphones of this closed type, sounds from outside of the headphones are completely shielded off. For this reason, the listener using these headphones is shut off from the outside and is thus subjected to a feeling of isolation, which gives rise to an unnatural sensation and other objectionable features of sound listening.
Accordingly, open-back type headphones, in which their backs are open so that the listener can hear some back or ambient noises also and therefore does not feel isolated, have been proposed and reduced to practice.
These open-back headphones, however, have been accompanied by certain problems. Since some sound leaks out from the headphone structures through the open backs to the outside, this feature becomes a disadvantage in cases where complete prevention of such leakage of sound out of the headphone is desired. Another problem is that, since sounds enter through the open backs of the headphones, sounds being listened to through the headphones are impaired by interference due to noise when excessive noise enters from the outside. Furthermore, in cases such as that where monitoring is being carried out with these headphones as sound is being recorded by means of a tape recorder, the sound from the outside to be recorded, noise, and other sounds are all heard, whereby in some cases the monitoring sound cannot be accurately grasped, and proper control of recording level cannot be achieved.